mysql2date uses strtotime and the future date could return false which would update the status of the future post to publish.

This is probably related to the date limitation for 32-bit systems, as described ​on php.net:

The valid range of a timestamp is typically from Fri, 13 Dec 1901
20:45:54 UTC to Tue, 19 Jan 2038 03:14:07 UTC. (These are the dates
that correspond to the minimum and maximum values for a 32-bit
signed integer.)

Since that's still fine given the current date, it might be a minor issue, but it's being exposed in a use case such as the import process where a future post is being published instead while migrating to another site.

For that specific use case scenario adding a non-false check would help, but is probably an overhead: